Electronic circuits may need to be provided with a reference voltage in order to function properly. Optimally, such a reference voltage is stable over time and not dependent on e.g. variations in ambient temperature. Such reference voltages are normally provided using various bandgap voltage reference circuits in which transistors and suitable resistors are arranged such that one variation by temperature cancels, or at least to a first order compensates for, another variation by temperature, thereby leading to a temperature-independent current which may be converted into a temperature-independent reference voltage. In such conventional bandgap voltage reference circuits, the current may be dominated by diffusion which may be suppressed at low temperatures (<50 K) thereby making the bandgap voltage reference circuits unsuitable for low-temperature electronics.
As an alternative, a stable voltage may be generated at low temperature by using circuits utilizing the Josephson effect in which a generated current depends only on applied RF frequency and fundamental constants. Such circuits, although functional also at low temperature, may be complex and require advanced control electronics in order to work.
There is therefore a need for an improved way of generating of a stable voltage reference at low temperature.